As a conventional wheel which reduces a road noise due to an air column resonance inside a tire air chamber, a wheel for a vehicle having already been disclosed by the present applicant is known in which an additional air chamber member functioning as a Helmholtz resonator in a tire air chamber is fixed to an outer circumferential surface of a well portion (for example, see Patent Literature 1).
This wheel includes a first vertical wall surface which is formed to extend in a circumferential direction of the outer circumferential surface on a vertical wall vertically provided on the outer circumferential surface of the well portion, and a second vertical wall surface which is formed to extend in the circumferential direction on a rising portion formed at one end of the well portion and faces the first vertical wall surface in a width direction of the outer circumferential surface. Moreover, a groove is formed to extend in the circumferential direction on the first vertical wall surface and the second vertical wall surface, respectively, and the additional air chamber member is fitted between the first vertical wall surface and the second vertical wall surface.
Also, the additional air chamber member includes a main body made of resin which is composed of an additional air chamber and a communication hole communicating the additional air chamber with the tire air chamber. Moreover, the additional air chamber member includes a first edge portion which is formed to extend from the main body toward the first vertical wall surface and to extend in the circumferential direction, so as to be fixedly engaged with the groove on the first vertical wall surface. In addition, the additional air chamber member includes a second edge portion which is formed to extend from the main body toward the second vertical wall surface and to extend in the circumferential direction, so as to be fixedly engaged with the groove on the second vertical wall surface.
Furthermore, the additional air chamber member includes a protruding portion serving as a so-called rotation-stop, which protrudes from the edge portion in a wheel width direction to be fixedly engaged with the vertical wall surface, so as to restrict movement of the additional air chamber member to a wheel circumferential direction.
The additional air chamber member of the vehicle wheel thus configured (for example, see Patent Literature 1) is often fixed to the well portion with a predetermined pusher (pressing device). FIG. 11A to be next referred to is a perspective view for explaining a mounting method by which an additional air chamber member 110 in a conventional vehicle wheel is mounted on a well portion 11c. As shown in FIG. 11A, the mounting method of the conventional additional air chamber member 110 includes inclining the additional air chamber member 110 so as to allow an edge portion 114a of the additional air chamber member 110 to come close to the well portion 11c and then allowing a protruding portion 118 provided on the edge portion 114a to be fitted in a cut-out portion 120 formed on the well portion 11c. At the same time, a portion of the edge portion 114a in the vicinity of the protruding portion 118 is fitted in a groove (not shown) on a first vertical wall surface 116a. 
Then, a pusher 60 is pressed against an edge portion 114b of the additional air chamber member 110, thereby allowing the entire edge portion 114a to be fitted in the groove on the first vertical wall surface 116a and allowing the entire edge portion 114b to be fitted in a groove (not shown) on a second vertical wall surface 116b. This allows the additional air chamber member 110 to be fixed to the first vertical wall surface 116a and the second vertical wall surface 116b of the well portion 11c. 
Incidentally, it is preferable that the additional air chamber member in the conventional vehicle wheel (for example, see Patent Literature 1) is a blow-molded component made of resin from a standpoint of weight saving, reduction in production cost, securing of airtightness of an additional air chamber formed inside, and the like.
However, as for the blow-molded additional air chamber member, in a cutting process at a cut-off section for separating a molded portion from an unnecessary resin portion, a so-called burr remains on the molded portion.
More specifically, burrs remaining on leading ends of the edge portions 114a, 114b graze against the first and second vertical wall surfaces 116a, 116b to be string-like burrs in the course of the mounting shown in FIG. 11A, which are removed from the edge portions 114a, 114b. When the removed string-like burrs are caught between a bead of the tire and a bead seat of the wheel, there is a possibility that a slow leak of air pressure of the tire is caused. Moreover, when the removed burrs gain entry to a tube member, there is also a possibility that sound deadening performance is deteriorated.
In view of this, it is preferable that when the blow-molded additional air chamber member is made into a product, the edge portions 114a, 114a are shaped.
FIG. 11B is a schematic view showing a leading end of the edge portion 114a which has been shaped, and is a schematic view of the edge portion 114a viewed from the wheel circumferential direction in FIG. 11A. In FIG. 11B, reference sign 125a denotes an upper plate constituting the additional air chamber member 110, and reference sign 125b denotes a lower plate.
As shown in FIG. 11B, when the leading end of the edge portion 114a is shaped, a portion of the leading end including a burr 117 is cut off along a cutting line 115 as the boundary. This shaping allows an abutting face on which the burr 117 does not exist, relative to the vertical wall surface 116a, to be formed on the leading end of the edge portion 114a. That is, a slow leak of the tire air pressure due to the removed string-like burr 117 is reliably avoided.